popular tourist destinations on the wild and exciting quest to make web maps in fewer tries
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README.md

What kind of data do you have?

Points

  • How much data?
    • Just enough
    • Too much in a confusing way, but each points data is important?
    • Too much and the points have some value that can be aggregated
      • Create hexbins of your points with the QGIS hexbin plugin, to make polygons. Start again at Polygons
    • Too much and the points just represent presence - like tweets
    • Tons of data, and you don't need labels? Use tippecanoe.

Polygons

  • How much data?
    • Just enough
      • Convert the data to GeoJSON & make a simple Leaflet map
    • Too much, the polygons have necessary detail
    • Too much, the polygons have unnecessary details

Attributes

  • What kind of attributes?
    • Absolute numbers
      • Convert the points to centroids with QGIS and start from Points
      • Normalize absolutes to rates by dividing over polygon area, and start from Rates
    • Rates or Categories
    • Temporal data - values over time
    • Multivariate data: like counts of different species or ethnicities
    • Names of places, like countries
      • With IDs:
        • ISO2 or ISO3 codes
          • Download Natural Earth data at the right level, join with QGIS, and start again at Polygons
        • ZIP codes
          • Download ZCTAs and join
      • Without IDs
        • Find data with IDs, or manually join with polygons
    • Addresses

Lines

  • Small amounts of data: use Leaflet
  • Lots of data, or need line labels (are they streets?)? Use TileMill
  • Tons of data, and you don't need line labels? Use datamaps.

Raster

  • Already georectified & cleaned (from satellites or fixed-up sources)
  • Raster images from drones
  • Raster images from scanned maps

A format that I can't read

  • Install GDAL and use ogr2ogr to convert the file. If you can't install this, you can use it online with Ogre
  • Commercial tools:
  • Ask your source for a better file format

OpenStreetMap

  • I want raw data right from the source, up to the minute, in its original form? planet.osm
    • Drawbacks: downloads are very large and require specialized tools to process
  • I want raw data for subsets of the world: Geofabrik extracts or Mapzen metro extracts
    • Drawbacks: only includes predefined areas, not as up-to-date as Planet.osm
  • I want data useful for fast basemaps, already processed into vector tiles: Mapbox
    • Drawbacks: doesn't include all features or all tags on features, only those appropriate for visualization
  • I want raw data as tiles, which include more data and complete tags: OSM QA Tiles
    • Drawbacks: much larger & slower than tiles designed for visualization
  • I want a specific subset of data by area, filter, and want the newest data possible: Overpass
    • Drawbacks: can't return country-sized chunks of data, only smaller subsets
  • I want filtered, up-to-date extracts in extra formats like KMZ, Garmin Image, etc: HOT Export Tool
    • Drawbacks: can't do arbitrary regions

I don't have data yet

Visualization defaults

  • Projection:
  • Colors:
  • Scales:
    • For any data
      • Try linear first
      • Then quantile
    • For data of rates or compounding values
      • Try log and power scales
  • Points:
    • Start with normal circles with no strokes
    • Scale points by area, not diameter
  • Flair:
    • Only add a north arrow if north isn't up
    • Always attribute your data, especially OpenStreetMap, to avoid the nerd wrath
    • If it zooms, add visible zoom controls. Pan isn't necessary, but not everyone has a scroll wheel / multitouch